CN1063892C - AM-FM transmitter power amplifier using class-BC - Google Patents
AM-FM transmitter power amplifier using class-BC Download PDFInfo
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- CN1063892C CN1063892C CN95196600A CN95196600A CN1063892C CN 1063892 C CN1063892 C CN 1063892C CN 95196600 A CN95196600 A CN 95196600A CN 95196600 A CN95196600 A CN 95196600A CN 1063892 C CN1063892 C CN 1063892C
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/60—Amplifiers in which coupling networks have distributed constants, e.g. with waveguide resonators
- H03F3/602—Combinations of several amplifiers
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
- H03F1/02—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
- H03F1/0205—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in transistor amplifiers
- H03F1/0211—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in transistor amplifiers with control of the supply voltage or current
- H03F1/0244—Stepped control
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F2200/00—Indexing scheme relating to amplifiers
- H03F2200/516—Some amplifier stages of an amplifier use supply voltages of different value
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F2200/00—Indexing scheme relating to amplifiers
- H03F2200/541—Transformer coupled at the output of an amplifier
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F2203/00—Indexing scheme relating to amplifiers with only discharge tubes or only semiconductor devices as amplifying elements covered by H03F3/00
- H03F2203/30—Indexing scheme relating to single-ended push-pull [SEPP]; Phase-splitters therefor
- H03F2203/30048—Indexing scheme relating to single-ended push-pull [SEPP]; Phase-splitters therefor the SEPP amplifier has multiple SEPP outputs from paralleled output stages coupled in one or more outputs
Abstract
A power amplifier circuit for efficiently generating an output signal into a load at more than one alternative power level has at least two amplifiers, each having optimum efficiency at different power output levels. The power amplifier circuit may be operated in several modes, including activating one amplifier during an entire cycle of an input signal to be amplified, or alternatively activating one amplifier based on a control signal that is independent of the amplified output signal. In either case, remaining amplifiers are deactivated. Coupling between the amplifiers prevents deactivated amplifiers from impeding the flow of power from the activated amplifier to the load. In another aspect of the invention, optimum efficiency at different power output levels is achieved by means of coupling each amplifier to a common power source and to the load via an impedance matching circuit, the impedance transformation being different for different amplifiers. The impedance matching circuit may comprise a push-pull transformer having taps to provide different turns ratios between respective amplifiers and the load. Alternatively, the matching circuit may comprise a number of quarter-wavelength lines each coupled at one end to the load and at the other end to one of the amplifiers via a balun.
Description
Background
The present invention relates to a kind of radio-frequency power amplifier, this amplifier can efficiently move when being used for the signal of enlargement range change, when amplifying the signal of fixed amplitude, can be transformed into more effective mode of operation.The invention still further relates to a kind of like this radio-frequency power amplifier, this amplifier be when need providing higher efficient when carrying out work under the output level state intermittence, and this had not only comprised signal fixing but also amplitude that comprise variation.
The radio transmission of signal and information is to produce by this signal being appended on the rf wave that is called as " carrier wave ", and additional this information processing process is called " modulation ".The most frequently used modulator approach is the type of two kinds of special uses, is known as amplitude modulation(PAM) (AM) and frequency modulation(FM) (FM) separately.
For AM, just the amplitude of radio frequency (RF) carrier wave or intensity change with the information carrying signal, and the frequency of this RF carrier wave is fixed.And for FM, just the frequency of RF carrier wave changes, and its amplitude is fixed.
Frequency modulation(FM) is one type widely of fixed amplitude modulation, and wherein information is carried in the variation at the phase angle of this carrier wave.Modulate at fixed amplitude that to design an effective transmitter be the easiest, generally their design can be best, can use one and only provide maximum efficient on an output power levels.
Amplitude modulation(PAM) is more difficult to be produced discretely, and requires different transmitter design usually.
The modulation type of a kind of more general being called " complex modulated " (complex modulation) had both allowed the changes in amplitude of carrier wave, allowed the phase angle variations of carrier wave again.This kind modulation type requires to use the transmitter power amplifier of " linearity " mode, so that reproduce the modulated amplitude of this input wave mode exactly, and wish to get high efficient thus and keep simultaneously linear operation and avoid cross modulation distortion be the most the difficulty.Belonging to such modal a kind of modulation is SSB (monolateral band) modulation.
Many in the art different RF power amplifier technologies are well-known.Now these technology will be described.
1. high level modulation
The valid approach that produces the high power am signals is called as the high level modulation method, is amplified and be used as the variable power supply of this high power RF amplifier forcefully at this low-frequency modulation signal itself.In this system, if locate C class state under the FM situation, this RF power amplifier can move on maximal efficiency, because the variation of power output produces by changing the input power that is directly proportional with the instantaneous power level that requires.
High level modulation device must produce the transmitter outgoing carrier power up to half, and becomes big, heavy and expensive element thus.This just makes this class A amplifier A be not suitable for being used in the prior application scenario of efficient to the consideration ratio generation power of size, weight or price.In this case, use the low level modulation scheme to replace sometimes.A kind of typical low level modulation scheme is the modulated RF carrier wave of generation amplitude on a low-power level at first, use the linear power amplifier that is similar to for example complex modulated (such as SSB) use that it is amplified to high power level then, and the efficient of this method is unessential when low-power level is modulated.
2. linear power amplifier
Such linear power amplifier is operated in category-A or the category-B state that people are familiar with on traditional form.
2.1 category-A efficiency power amplifier
The result that class-a amplifier is biased is the continuous consumption electric current, even when not requiring when producing any power output, also consume half the average current that equals peak current that it extracts when producing peak power output.When with the AC input signal of an amplitude peak-when for example a sinusoidal radio carrier frequency signal drives, this class-a amplifier electric current is zero and double between this average current and swing, but on average remaining unchanged on the one-period of this input signal.Signal power is output as maximum in these cases, and efficient is 50% to the maximum.
When being driven by an AC input signal that is lower than this amplitude peak, this category-A electric current is swung between the part of corresponding average current, but average current is still constant.For example, suppose that the AC input signal is half a situation of amplitude peak, the category-A electric current is swung between 0.5 and 1.5 times of average current, but average current still equals this average (mean) electric current.Signal power is 1/4 of maximum power output under these conditions, and the identical high value of the current drain of power supply when remaining on maximum power output.Efficient reduces under lower output condition thus, and efficient has only 12.5% under the half amplitude point condition, 1/4 during for peak power output.
For avoiding distortion, must adjust such RF signal, this signal changes around an average amplitude on amplitude symmetrically by an am signals, amplitude peak from zero by average amplitude to doubling this average amplitude (promptly, amplitude from average-on average on average+mean change), thereby the peak amplitude that doubles this mean value is corresponding to the maximum power situation that is less than or equal to above-mentioned class-a amplifier.Like this, only provide its maximal efficiency 50%, and average average efficiency will be lowered on a modulation period at this category-A power amplifier of instantaneous peak value amplitude.At modulation signal is reticent, and amplifier is driven under half the condition of the average output level of RF that equals peak value RF output level (the not accent carrier wave condition of AM transmitter), only is 12.5% for the efficient that produces reticent carrier wave.
2.2 the efficient of category-B power amplifier
In the low efficient of the class-a amplifier on the mean value mainly is owing to do not reduce its power consumption when power output will be in low spot.This shortcoming is partly overcome by class-b amplifier.
Class-b amplifier is made up of two identical amplifier devices, and these two identical amplifier devices are pressed the push-pull configuration configuration, and just in time are biased on the working point that does not consume any power source electric current when not having the RF input drive signal.If this RF input drive signal swing is in positive direction, one of them amplifying device will begin to take electric current in proportion, and another works on negative half period.
Each device is taken half sinusoidal current impulse string of the mean value with 1/ π times peak value in class-b amplifier like this.The total current that two amplifying devices are taken from power supply is 2/ π peak current.This total current increases the signal that is delivered to load (antenna) thus pari passu along with the RF drive level increases, till the available no better than supply voltage of output voltage swing that produces at the load impedance two ends.And the further increase that surpasses this RF drive signal will not increase the voltage at load two ends, and it is saturated that this amplifier is considered to, or " slicing ".Use for linear modulation, amplifier can not be driven to this scope, otherwise will produce modulation distortion.
Equal supply voltage V by each peak inrush current of recommending the device extraction before the slicing
0Divided by load impedance R
L
I
max=V
0/R
L
Average current is 2/ a π times peak current, and we obtain Mean Input Power by power supply:
V
0·I
max·2/π=(2/π)V
0 2/R
L
And at this load R
LThe middle AC power that produces is 0.5V
0 2/ R
LIt is π/4 or 78.5% that the ratio of getting output AC power and power consumption provides efficient.
By observed power consumption and proportional the reducing of output voltage swing, and square proportional efficient that reduces to calculate when being lower than peak amplitude of power output and output voltage swing.Efficient reduces with output amplitude is linear like this, makes equaling on the average amplitude partly of peak value, and efficient equals peak efficiencies partly, is 0.5 π/4 or 39%.
This is significant an improvement for 12.5% efficient of class-a amplifier on half-peak value amplitude leyel, and this be since class-b amplifier reduced it with the electric current that requires proportional extraction.Yet compare with 78.5% efficient of category-B power amplifier under full output state and to remain inefficient.The theoretic efficient of non-linear C class A amplifier A even better near 100%, therefore, is compared the transmitter for low level modulation AM with the FM transmitter, exists big loss on efficient.
3. load impedance conversion
Sometimes must use the occasion of FM signal work with the work of AM signal sometimes at a transmitter, and the AM design efficiency is lowly still relevant with the FM pattern usually.This is can be problematic in the such application of for example portable radiotelephone transmitter, because small size requires and require single power amplifier effectively by AM that replaces and the work of FM mode of operation to the trust of battery supply, and has identical average power output level in two kinds of situations.
If a class-b amplifier is used for 1W carrier power AM transmitter, then under the modulation crest state that amplitude doubles, must have the ability to produce the power of 4W.If a such amplifier is used to the FM transmitter of 1W, then its efficient in theory only may be 39% rather than 78.5%.Handheld wireless phone for example with battery operated equipment in, both can select power amplifier to operate in 1W and efficient is half, also can select the power amplifier of 4W total efficiency, both have passive influence to battery life.
More known technology will illustrate this problem.
That grants Schwent has described a kind of amplifier in this U.S. Pat 5,060,294 as a reference, and wherein, load impedance makes the first saturated value of this amplifier and preventing conversion between the second saturated value of this amplifier.This makes this amplification both can use the signal of fixed amplitude, also can use the signal of amplitude of variation.Yet, the not mentioned alternative power output level of Schwent about being issued in the situation of improving efficient.
Grant Dent at this also as a reference U.S. Patent application (application number 08/061,345, May 17 1993 applying date) a kind of amplifier is disclosed, this amplifier uses on the output power levels of alternative and is transformed into the load impedance that obtains optimum efficiency, this alternative output power levels both corresponding to the linearity under two situations using the amplitude of variation signal (for example, category-B) the amplifier work of pattern, again corresponding to the amplifier work of saturated (for example, the C class) pattern under two situations using the fixed amplitude signal.But be to use impedance transformation to have some defectives, comprise loss relevant and unexpected transformation from a kind of pattern to another kind of pattern with conversion.In addition, the efficient of this class A amplifier A is not high when being operated in linear model.
Therefore expectation provides a kind of RF power amplifier, it can be on a power level by linear (for example, category-B) pattern work, and on another output power levels by saturated (for example, the C class) pattern work, not working load impedance transformation or alternating source voltage.
General introduction
Therefore one object of the present invention is to provide a kind of power amplifier, and it both can be used for the signal of enlargement range modulation by linear model work, can still not have very actual accessible efficient under the FM pattern does not reduce the situation of power level again.
Another object of the present invention is to provide a kind of power amplifier, it is efficiency operation on full power level and another kind of lower power output level.
A further object of the present invention is to provide a kind of power amplifier, it at linearity or nonlinear model than only requiring that the typical B class A amplifier A that single power supply voltage powers up more effectively works.
Press one aspect of the present invention, an efficient BC class A amplifier A that is used for the input signal of enlargement range variation comprises first power amplifier that input signal is amplified to first output level that is operated in the category-B pattern; What be operated in the C quasi-mode is used to amplify second power amplifier above the input signal of this first output level; And the coupling device that the output of first and second power amplifiers is coupled to a common load impedance.
Press another aspect of the present invention, power amplifier of the present invention comprises two amplifiers at least, each is preferred for power supply on the different capacity level, these two amplifiers are coupled to a load regularly together by suitable coupling network, this coupling network has such performance, therefore the i.e. output impedance that is not driven or is not activated of one of at least two amplifiers do not stoped by driving one of two amplifiers power is delivered to this load by this coupling network conversion at least.High efficiency on the different output power levels of another kind is to reach by select starting one of two amplifiers that full expection power output may be provided.
By one side more of the present invention, coupling network comprises having a centre tapped push-pull transformer that is used for from a power supply received power, and this power supply is a public power of receiving all amplifiers.Load is coupled to this Secondary winding of transformer, and each amplifier is coupled to the respective taps on this primary winding, and therefore, the number of turns between any given amplifier and load is than the number of turns ratio that is different from other amplifiers.
By one side more of the present invention, this coupling device comprises two impedance matching networks at least, each is coupled so that from the public power received power and be coupled to load, also be coupled to a corresponding amplifier, wherein, each impedance matching network is carried out different impedance transformation between a load and a corresponding amplifier, so any one amplifier power output level of reaching optimum efficiency is different from the power output level of other amplifiers.
By one side more of the present invention, each impedance matching network comprises with the matching ratio being a quatrter-wavelength line of feature; Balanced-to-unbalanced transformer (Balun) with primary and secondary winding.Secondary winding is coupled to this 1/4 wavelength line.Elementary winding has a center coupling tap, so that from a public power received power.Each is coupled to corresponding of at least two amplifying devices residue tap on elementary winding.The matching ratio of any one impedance matching network is different from the matching ratio of other impedance matching networks.
By one side more of the present invention, a power amplifier circuit comprises two amplifiers at least, each is coupled to a load, and on different power output levels, has optimum efficiency, this power amplifier circuit is by a kind of method work, and therefore an output signal can be added to this load on more than one other power level.This method comprises the step of one of selecting at least in two amplifiers and starting selected amplifier, so that the whole input signal cycle that the amplifying device that is activated by this is amplified produces an amplifying signal.With this setting up procedure while, all non-selected amplifiers do not start.The signal that is exaggerated afterwards is added to load from the amplifying device that this is activated, and the amplifier that is not activated will prevent to consume the signal power from being exaggerated signal.
By one side more of the present invention, a power amplifier comprises two amplifiers at least, each is coupled to a load, and on different power output levels, has optimum efficiency, this power amplifier circuit is by a kind of method work, so that the output signal of power amplifier circuit is added to load on more than one other power level.This method comprises that generation is independent of a control signal of this output signal and uses this control signal to select the step of one of at least two amplifiers.Selecteed afterwards amplifier is activated, so that produce an amplifying signal, with this setting up procedure while, all non-selected amplifiers do not start.This signal that is exaggerated is added to load by the amplifier that starts, and the amplifier consumption that prevents from not to be activated is from the signal power that is exaggerated signal.
By of the present invention more on the one hand, the amplifier of any the foregoing description can be by linear model work, or they can be by saturation mode work.
Brief description of drawings
Objects and advantages of the present invention will be read following detailed description in conjunction with the drawings and be understood, and these accompanying drawings are:
Fig. 1 is the schematic diagram by a kind of linear BC class A amplifier A of one aspect of the invention;
Fig. 2 is the schematic diagram by the present invention's a kind of BC class high-frequency amplifier on the other hand; And
Fig. 3 (a), 3 (b) and 3 (c) are the schematic diagrames by the amplifier of the use line transformer of further aspect of the present invention.
Describe in detail
For overcoming above-mentioned 78.5% the efficient limit of linear class-b amplifier, the present invention includes a amplifier (being known as a linear BC class A amplifier A thus) by category-B and the work of C class mixed mode, as this with reference to Fig. 1 described.An amplifier like this uses first pair of push-pull transistor or other devices, so that 0 and ± α doubly produces signal output waveform between maximum, use second pair to recommend device afterwards, so that be created in ± α times maximum is outer up to maximum plus or minus voltage value signal waveform values.
As shown in Figure 1, first pair of complementary transistor 1,2 is connected ± α V
MaxThe power voltage line of symmetry between, and the load voltage that will order at A of the excitation by drive circuit 8 or upwards be drawn to+V
Max(transistor 1 conducting) or be drawn to downwards-V
Max(transistor 2 conductings).Part that like this should the work period is used this transistor 1,2 by the linear operation mode of the category-B of recommending of the single termination of being familiar with.To this kind mode of operation, voltage can be at approaching ± α V
MaxBetween change, in transistor 1,2 or diode 6,7, cause that free voltage falls, if α V
MaxSpecific loss is much bigger, then can ignore this voltage drop.If output voltage changes by sinusoidal wave form in this pattern, the rms power output will for:
And be from the average current consumption of every power circuit:
By with this power output divided by power consumption, obtaining efficient is π/4, the limit theory value of category-B mode of operation that Here it is.
Yet for the of the present invention linear BC class A amplifier A of Fig. 1, by starting second pair of transistor 3,4, the amplitude of oscillation of output voltage can be increased to and be higher than α V
MaxDrive circuit 8 is by a negative-feedback signal 9 control, second pair of transistor 3,4 of deactivation when its detects the voltage that desired output voltage can provide greater than first pair of transistor 1,2 with box lunch.When the output voltage of ordering at A surpasses+α V
Max, and upwards increase to+V owing to start transistor 3
MaxThe time, diode 6 becomes reverse bias, stops transistor 1 thus from placed in the middle+α V
MaxPower line extracts power, even transistor 1 continues to be biased conducting state.And transistor 3 is from higher+V
MaxPower line provides load current in this zone.
Equally, when being lower than negative peak-α V that transistor 2 can provide
MaxAnd down to-V
MaxPoint on start transistor 4 when obtaining load voltage, diode 7 becomes reverse bias, will stop transistor 2 from placed in the middle-α V thus
MaxPower line extracts electric current, even transistor 2 continues to be biased conducting state.And transistor 4 is from more negative-V
MaxPower line provides load current in this zone.
If the output voltage that produces is in this way at ± V
MaxBetween change, then part-time is from four power line current sinkings, but owing to be better than pure category-B pattern, when
The time, efficient will then be increased to 85.6% theoretical value, for pure category-B pattern, electric current is only taken from the power line that has reduced, to this part time output voltage be in+/-α V
MaxBetween.For amplitude is the signal of pure sine wave, and the testing efficiency on experimental prototype conforms to 85.6% theoretical value.
There is some defective in linear BC class A amplifier A described above for very high frequency operation.At first, the counter-rotating that the state of the art of semiconductor diode is very fast to the RF unallowable state is still more for microwave frequency; Secondly, the BC class A amplifier A of Fig. 1 is subjected to the restriction of the RF application of audio frequency or intermediate frequency usually.Circuit requirement provides supply voltage placed in the middle in addition.Press another aspect of the present invention, these defectives will be eliminated.
Referring now to Fig. 2, a preferred embodiment of the present invention has several amplifiers FET of push-pull configuration (preferably dispose to), and each is coupled so that power is delivered to load R
L10.Drive circuit 11 receives the input signal 26 that is amplified by power amplifier.Drive circuit 17 also receives control signal 25, and which is activated (being FET 12,13 or FET 14,15) to FET in any given moment in this circuit indication.As inciting somebody to action in greater detail below, can produce control signal 25 by being independent of the instantaneous output signal that is added to load 10.Drive circuit 17 usefulness control signals 25 are delivered to input signal 26 in the amplifier of selecting startup.This drive circuit 17 also produces signal to be ended to guarantee non-selected amplifier, preferably applies the grid that a negative bias is pressed onto this non-selected FET for this reason.This drive circuit 17 also comprises the device that is used under the high-frequency work situation coupling and tuning this FET grid input capacitance.Those personnel that possess common specialty will design a drive circuit that works by these parameters easily.
By the present invention, must provide the problem of voltage placed in the middle (as shown in fig. 1) to advise recommending first couple of FET 12,13 of output transformer 11 and solving by being connected to high frequency.The public power (not shown) provides power (V to the centre cap of the elementary winding of transformer 11
Max).The number of turns of the transformer between first couple of FET 12,13 and load 10 is than being N--0--N:M.Like this when signal conduction of the self-driven circuit 17 of FET 12 origin, load voltage can be 0 and (M/N) V
MaxBetween change.
Equally, when drive circuit 17 alternately makes FET 13 conductings load voltage can 0 and-(M/N) V
MaxBetween change.
If load voltage in sinusoidal wave mode at ± (M/N) V
MaxBetween change, this means that this amplifier by the work of category-B pattern, has 78.5% theoretical efficiency on following output power levels
Start FET 14 or FET 15 by being used for the proper signal of self-driven circuit 17, load voltage can be at ± (M/N) V
MaxChange between/α the value, because this FET 14,15 uses the different transformer number of turns than α N--0--α N:M.When FET 14 conductings produce maximum positive voltage at the load two ends, FET 12 will have and equal-V
MaxThe negative drain voltage of (1-α)/α.
For preventing FET 12 conducting and reduce circuit efficiency thus and make the output signal distortion under negative drain voltage condition, grid voltage must remain below the state of this drain voltage by drive circuit 17, equally, suppose the structure to block CMOS technology, semiconductor chip voltage must remain below maximum negative drain voltage.For example, for V
Max=+8V and α=
Drain electrode and the substrate of the FETS that disconnects must keep below pact-3V.For this substrate, this condition can reach by allowing the unsteady method that breaks away from decoupling capacitor 22 of this substrate, and this decoupling capacitor will be by additional drain electrode-substrate diode 18,19,20,21 rectified action is charged to maximum negative drain voltage.
On the other hand, can use optional diode 23,24 (dotting), their function class is similar to the diode 6,7 shown in Fig. 1.When FET 14 had been taken over load by its corresponding driving signal indication, diode 23 prevented that FET 12 from taking electric current, even this FET 12 keeps the biasing of conducting.Similarly, when FET 15 had been taken over load by its corresponding driving signal indication, diode 24 prevented that FET 13 from taking electric current, even this FET 13 keeps the biasing of conducting.
This scheme can be simplified bias unit and drive circuit, for very high frequency(VHF), and microwave frequency for example, optionally diode 23,24 can become the frequency limitation element, and this is because they can determine from the speed of forward conduction to the reverse-conducting conversion.Using optional diode 23,24, may be only solution for the application of lower frequency and high power supply voltage, for example when amplifier of the present invention is used as an efficient sinusoidal DC-AC power supply changeover device; And when omitting this optional diode at 23,24 o'clock, may be only solution for the frequency applications of low supply voltage, for example for the power amplifier of the transmitter in battery powered mobile radiotelephone.
Amplifier of the present invention shown in Figure 2 can be pressed any work of following seven kinds of patterns:
ⅰ) linear model (being A, category-B or AB class) is in the first power level state, and only FET 12,13 is driven, and FET 14,15 is biased cut-off state.
ⅱ) the same pattern just is in saturation condition (that is, FET 12,13 is driven to the amplitude limit state).
ⅲ) linear A, category-B or AB class are in the second power level state, and only FET 14,15 is activated, and FET 12,13 keeps the bias off state.
ⅳ), just be in saturation condition (being that FET 14,15 is driven to the amplitude limit state) with (ⅲ) pattern.
ⅴ) linear BC quasi-mode, FET 12,13 is driven to conducting, only is used to have ± (M/N) V
MaxBetween the value the output waveform part, FET 14,15 conductings afterwards are used at the output waveform voltage that exceeds outside the above-mentioned scope.(this pattern is corresponding above about the described mode of operation of Fig. 1)
ⅵ), just be in saturation condition (being that FET 14,15 is driven to the amplitude limit state) with (ⅴ) pattern.
ⅶ) for the range signal by pattern (ⅰ) work is changed, as long as the output amplitude of knowing requirement in advance superthreshold not, and for make by pattern (ⅲ) or (ⅴ) range signal of work change, as long as desired output amplitude is exceeded this threshold value by expectation.
On the principle, all above patterns all can be selected by the appropriate control signals 25 relevant with the desired output power level.But in fact in a given job, will not require all patterns.For example, in the mobile phone transmitter applies, BC quasi-mode (ⅴ) and (ⅵ) on typical 1GHz frequency, will be difficult to realize.Digital amplitude of variation and the simulation fixed amplitude double-mode mobile telephone in main interested pattern be (ⅰ), (ⅱ), (ⅲ) with (ⅶ), for example in the dual-mode telephone described in this United States Patent (USP) (application number 07/967,027) as a reference.
Preference pattern (ⅰ) when under being no more than the first power level situation, requiring to use the amplitude of variation modulation (compare power level reduces with the figure pattern full-load power).When continuously but (for example require the fixed amplitude modulation under the FM power level situation that is lowered, advanced mobile phone service (AMPS) FM modulation) energy use pattern (ⅱ) time, and when under the figure pattern situation, periodically requiring higher peak power, use pattern (ⅲ).Preference pattern will form above-mentioned pattern (ⅶ) in this way.
Can select the relation of α value with the accurate requirement between the full-load power level of the peak power that obtains full-load power numeral (amplitude of variation) pattern and FM pattern.For example a kind of hand-held can the taking in the phone by the above Application No. of quoting as proof 07/967,027, the full-load power level that the FMAMPS pattern is sent antenna is 600mw.Full power on average also is 600mw in figure pattern, but because changes in amplitude, peak power is 1.2w.Compare with pattern (ⅰ) or power level (ⅱ) like this, it is approximate to choose α
Make pattern (ⅲ) reach the max power level of twice.Make its output when the downward grade level drops of fully loaded output is hanged down, can use half-power linear model (ⅰ) when taking phone by the base station domination.In this way, FM pattern or the efficient that has been lowered the figure pattern of power improve significantly.
On the high-frequency of for example about 1GHz, realize transformer, for example transformer 11 is difficult, this is because on those frequencies, they are tending towards changing in quality into the individual pen element.Like this, press another aspect of the present invention, impedance conversion between amplifier and load usually for example the transformer number of turns implement than M/N, but implement with matching network, this matching network can be inductive-capacitive filter or the such transmission circuit network of 1/4 wavelength transformer for example, matching stub (Stub) or band spider lines.A kind ofly be suitable for realizing that the Utopian preferred embodiment of the circuit of BC class A amplifier A of the present invention is illustrated among Fig. 3 (a) and 3 (b).
It is Zo that Fig. 3 (a) expression one first push-pull transistor amplifier is connected to characteristic impedance to 32,33 by a suitable balanced-to-unblanced transformer (balun) 30
11/4 wavelength transformer, the matched transmission line Zo of 1/4 wavelength by having T joint 38 is connected to the load (not shown) that impedance is Zo afterwards.One second push-pull transistor amplifier passes through balanced-to-unbalanced transformer 31 and 1/4 wavelength transformer Zo to 34,35
2Be connected.In this way, transistor 32,33 is considered as load impedance Zo by balanced-to-unbalanced transformer
1 2/ Zo, and transistor 34,35 is considered as load impedance Zo by balanced-to-unbalanced transformer 31
2/ Zo, crystal amplifier to linearity (category-B) power output of 32,33 Utopian theory is like this
0.5·V
max 2·Zo/Zo1
2
And transistor 34,35 can produce power equivalently
0.5·V
max 2·Zo/Zo2
2
Suppose that balanced-to-unbalanced transformer 30,31 has (1+1): 1 conversion ratio.
If start transistor to 32,33 by 36 of drive circuits, and drive circuit 37 maintenance transistors 34,35 bias offs, then the drain electrode of the open circuit of transistor 34,35 will be by 1/4 wavelength transformer Zo
2Convert short circuit in junction with the Zo line, and after connect 38 places by this 1/4 wavelength line load T shape, turn back to open-circuit condition.Like this transistor 34,35 be biased by the time do not influence power and be sent to load from transistor 32,33.In addition, suppose Zo
2＜Zo
1, then when transistor 32,33 produces its maximum output, the voltage swing that produces on transistor 34,35 will be no more than V
Max, the drain electrode of transistor 34,35 never becomes negative thus.
If transistor 34,35 is started by its corresponding driving circuit 37 now, connecting 38 places T shape provides power to load, and Zo
2＜Zo
1, then can produce higher power.This power is owing to be multiplied by the factor (Zo
1/ Zo
2)
2And it is higher, and when producing maximum output, transistor 32,33 drain electrode can be forced to and swing to negative voltage, make transistor 32,33 grid and substrate remain on the more negative voltage of the negative voltage swings more maximum than drain electrode, so that prevent to lower efficiency and to cause the undesirable conducting of distorted signals.Can understand this design thus allows transistor 32,33 to produce separately in load up to by Zo
1The power of first value of determining, in linear category-B pattern, maximal efficiency is 78.5% in theory, and transistor 34,35 can produce the power above this level separately, up to by Zo
2The second higher level of determining, and in this maximum, linear category-B output will also reach 78.5% category-B efficient in theory on this level.Might on two different possible power levels, reach maximum category-B efficient for device of the present invention like this.Press another aspect of the present invention, as be expanded the 1/4 wavelength line (Zo that other push-pull transistor amplifier is other to process by T junction (tee-ing) in this principle as shown in Fig. 3 (b)
3, Zo), (Zo
4, the Zo) points of common connection of arrival load.
Press another aspect of the present invention, another embodiment of equivalence on function of Fig. 3 (c) expression, but avoided T shape connecting line Zo.In this device, when transistor 34,35 is not driven and is in and disconnects drain electrode mode state following time, Zo is passed through in their open circuit output impedance
2Be converted into short-circuit condition, and its left hand end provides power by transistor 32,33 in load 39 right hand end.For other higher power mode, transistor 32,33 drain electrodes disconnect, and Zo is passed through in the drain electrode of this disconnection
1Be converted into short circuit, and transistor 34,35 provides power to its right hand end at load 39 left hand ends.
Those microwaves amplify the professional and technical personnel and will appreciate that, for illustration purpose, are Utopian operations.In fact, the FET of disconnection is not an open circuit, and replaces the parasitic capacitance output impedance of existence.But these parasitic output capacitances can be absorbed in the design of coupling between transistor and load or coupling network and go.The requirement that this network design must satisfy fair copy invention work is, for for the amplifier type of being described among Fig. 3 (a) or Fig. 3 (b), the matrix chain of the network between transistor drain and load (chain matrices) should have off-diagonal neutral element, and for for the circuit of being described among Fig. 3 (c), this matrix chain should have the neutral element of leading diagonal.Those of ordinary skills can use transmission circuit network or discrete reactance component or both to mix and design the suitable network that satisfies these requirements.Those skilled in the art also recognize by drive circuit 36, the push-pull transistor amplifier is to 32,33, with the amplifier of balanced to unbalanced transformer 30 formations and by drive circuit 37, the push-pull transistor amplifier is to 34,35 and the amplifier that constitutes of balanced to unbalanced transformer 31 each all can be equivalently replace with the complementary amplifier of single-termination, the diversity of recommending for example can constitute with complementary MOS transistor technology.Can use complementary bipolar or GaAs heterojunction bipolar transistor (HBT) to form the push-pull power amplifier of single-termination in addition; but in the case; as (diode 6 in Fig. 1; 7) the polyphone diode (not shown) that illustrates is required to protect this lower-wattage, and right collector-base junction avoids becoming forward bias, if in case the higher-wattage amplifier to work.
When each amplifier is pressed linear model work, but the enforcement of the power amplifier of all the invention described above can be pressed the signal of a kind of control amplitude of variation of three kinds of modes:
1) experience that has earlier of maximum output on demand only starts an amplifier or another one amplifier.This pattern for example can comprise uses an amplifier to be used for the duration (being equivalent to the duration in a whole input cycle) in the cycle of a whole output signal when selecting figure pattern and use another one amplifier when selecting simulation model; Perhaps when selecting the power level that reduces, use an amplifier to be used for the duration of a whole input signal cycle and use another one amplifier when selecting higher power level; Perhaps
2) on the different level of an individual signals wave period, dynamically start the right transistor of each amplifier, make and win to producing the load current of output voltage up to first level, and afterwards second pair take over and produce the load current of output voltage up to second level; Perhaps
3) dynamically select first pair of transistor or second pair of transistor, so that dynamically (for example, RF) but dynamically keep load current by the amplitude modulation(PAM) of relative expectation requirement output signal or the relatively slow markers of envelope by desired output instantaneous voltage.
In above the third situation, the at present common digital signal processor (DSP) that is to use reproduces the transferred signal of numeral, converts this digital signal to analog form so that drive transmission power amplifier afterwards before upconvert becomes desired output frequency signal.Be that to discern this power amplifier be the amplitude that is required to produce the first amplifier ability of surpassing for the DPS simple thing like this, and should be used for second more high-power amplifier as an alternative with producing a drive signal.Select to drive one or another amplifier in this case and be undertaken by the slow relatively markers of this modulation rather than in the markers in radio carrier frequency cycle, carry out.Get and make an example, a twotone stimulus shows 100% sinusoidal wave amplitude modulation(PAM), advantage that can following calculating amplifier actual efficiency of the present invention:
At first the twotone stimulus is calculated the efficient of the category-B of common prior art.
For formula V
MaxCos (ω
mT) cos (ω
cT) such output signal, ω
mBe this twotone interval half (half the two-tone spacing), and ω
cBe carrier frequency, RF cycle (ω
c) the DC electric current on average provide by following formula:
At ω modulation period
mOn average again, provide average DC electric current:
I
dc=4·V
max/(π
2·R
L)
The DC power consumption equals this current drain and multiply by supply voltage V
Max, that is:
P
dc=4·V
max 2/(π
2·R
L)
At RF cycle (ω
c) go up average power output and provide by following formula:
At (ω modulation period
m) on average provide average output power again:
P
out=V
max 2/(4·R
L)
Efficient is P like this
Out/ P
Dc=π
2/ 16 or about 61%.
Use the above-mentioned amplifier of the present invention that is operated in three-mode, the expression of power output is identical, and is the function of parameter alpha for the expression of DC power consumption.
When α was 0.659 value, efficient was 78.05% to the maximum.Amplifier of the present invention has like this improved the theoretical efficiency limit according to twotone test, from category-B 61% to 78% of amplifier of the present invention.
People will appreciate that the α value that makes the efficient maximum will depend on the amplitude statistics of the signal of being expected, like this, be different from a value of 0.659 for except that two sinusoidal wave and signal can be best.Other common signal statistics comprises Gauss (Gaussian) amplitude probability distribution, and can calculate above-mentioned situation one of α different optimum value.When the Gaussian Profile characteristic is its peak value when unrestricted, this experiment here can not be carried out, and is inevitable for some time slice amplitude limit therefore.Gaussian signal scale (scaling) also is another parameter that must select, so that make the amplitude limit total amount not produce excessive cross modulation distortion or excessive unnecessary spectrum component.The value of α will depend on this second parameter, and will exceed scope disclosed by the invention for all combinations of research, and this all combination can use above calculating as guiding to go to carry out by having this professional those of ordinary skill.
The variation that all are described in above specification, be included as and avoid inoperative distortion or the efficient of causing of reverse bias pair amplifier to reduce and all be considered to include within the scope of the present invention in the change aspect network or the device, these variations can be by the principle design of some those skilled in the art according to above general introduction.
The present invention is described with reference to specific embodiment.Yet for the professional and technical personnel, might go to implement the present invention by the concrete mode that is different from above preferred embodiment, and this to name a person for a particular job be to understand easily.Yet can do like this, but not break away from spirit of the present invention.Preferred embodiment is an explanation, should not be thought of as the restriction of where face in office.Scope of the present invention is given by additional claim, rather than top specification is given, and all variation and equivalent all meaning at this of being included in the claim scope are accepted.
Claims (19)
1. one kind produces the power amplifier circuit of output signal in the load effectively on the power level that replaces more than, comprising:
At least two amplifying devices, each has optimum efficiency on different power output levels;
The drive signal device is coupled to this at least two amplifying devices, is used for starting selectively any one of these at least two amplifying devices and suppresses all not amplifying devices of selected startup, wherein
This amplifying device that is activated produces output signal and is added to load; And
Selection is based on the amplitude of modulation signal, and this modulation signal has the frequency lower than carrier frequency, and this carrier signal is added to this power amplifier circuit as input signal; And
Coupling device, be coupled to each and load of these at least two amplifiers, be used for these at least two amplifying devices being coupled to this load, promptly by being activated amplifying device is not subjected to this repressed amplifying device to the signal power of load interference by a kind of like this mode.
2. press the power amplifier circuit of claim 1, also comprise the device that is coupled to these at least two amplifying devices, prevent that this repressed amplifying device from reducing the efficient of this power amplifier during the output signal voltage amplitude that is used for when output signal voltage amplitude that this amplifier that is activated produces is activated greater than this repressed amplifying device, producing.
3. by the power amplifier circuit of claim 2, wherein, this anti-locking apparatus applies the input electrode of a reverse biased to this repressed amplifying device, and the instantaneous output signal level that applies this reverse biased and power amplifier circuit is irrelevant.
4. by the power amplifier of claim 2, wherein, this anti-locking apparatus comprises the diode that is connected between the individual output of one of this coupling device and these at least two amplifying devices.
5. press the power amplifier circuit of claim 1, also comprise the device that is coupled to these at least two amplifying devices, prevent that this repressed amplifying device from making this output signal distortion during the output signal voltage amplitude that is used for when output signal voltage amplitude that this amplifier that is activated produces is activated greater than this repressed amplifying device, producing.
6. by the power amplifier circuit of claim 5, wherein should apply the input electrode of a reverse biased to this repressed amplifying device by anti-locking apparatus, the instantaneous output signal level that applies this reverse biased and power amplifier circuit is irrelevant.
7. by the power amplifier of claim 5, wherein, this anti-locking apparatus comprises a diode between the output that is connected one of this coupling device and these at least two amplifying devices.
8. by the power amplifier circuit of claim 1, wherein this coupling device is a push-pull transformer, and this transformer comprises:
A secondary winding is used to be coupled to load; And
An elementary winding, it has a centre cap that is coupled to input unit, and this at least two amplifying devices are coupled in all the other taps, make in first number of turns between first and the load of these at least two amplifying devices than being different from second number of turns ratio between second of these at least two amplifying devices and the load.
9. by the power amplifier circuit of claim 8, wherein, each of these at least two amplifying devices is a push-pull amplifier.
1O. power amplifier circuit by claim 1, wherein this coupling device comprises at least two impedance matching networks, each is coupled to input unit and load, and each also is coupled to corresponding one of these at least two amplifying devices, the impedance transformation that wherein is coupled to first impedance matching network of first amplifying device is different from the impedance transformation of second impedance matching network that is coupled to second amplifying device, the optimum efficiency of this first amplifying device occurs at first power output level thus, and the optimum efficiency of this second amplifying device occurs at second power output level, and this first and second power output level is unequal each other.
11. by the power amplification circuit of claim 10, wherein
Each of these at least two impedance networks comprises:
-1/4 wavelength line is a feature with a matching ratio; And
-balanced to unbalanced transformer has the secondary winding that is coupled to this 1/4 wavelength and has of being coupled to this input unit centre tapped and be coupled to the elementary winding of the tap of corresponding one remainder of these at least two amplifying devices; And
First of these at least two impedance matching networks has first matching ratio, and second of at least two impedance matching networks have second matching ratio, and first matching ratio is not equal to second matching ratio.
12. one kind is used for the method that control one power amplifier circuit generation output signal is gone to load on the power level that replaces more than, this power amplifier circuit comprises two amplifying devices at least, each is coupled to load, and each has optimum efficiency on different power output levels, and this method comprises the steps:
Select one of these at least two amplifying devices individual;
Start this selecteed amplifying device, so that produce the amplifying signal of the whole input signal cycle that the amplifying device that is activated by this is amplified;
With this setting up procedure while, suppress all not amplifying devices of selected startup;
To offer load from the signal that is exaggerated of this amplifying device that is activated; And
Prevent that this repressed amplifying device consumption is exaggerated the signal power of signal.
13., also comprise the step of the amplifying device that is activated by linear model control by the method for claim 12.
14., also comprise the step of the amplifying device that is activated by saturation mode control by the method for claim 12.
15. by the power amplifier circuit of claim 1, comprise the efficient BC class A amplifier A of the input signal that is used for the enlargement range variation, this BC class A amplifier A comprises:
-the first power amplifier is operated in the category-B pattern, is used for amplification input signal and makes it up to first output level;
Second power amplifier is operated in the C quasi-mode, is used for amplification input signal and makes it surpass this first output level; And
Coupling device is used for a common load impedance is coupled in the output of this first and second power amplifier.
16. by the power amplifier circuit of claim 15, in the BC class A amplifier A therein, when second power amplifier provided power output to arrive the common load impedance, this coupling device prevented this first power amplifier consumed power.
17. by the power amplifier circuit of claim 15, in the BC class A amplifier A therein, this coupling device prevents that this first power amplifier from making the output signal distortion that is added to this common load impedance by second power amplifier.
18. power amplifier circuit by claim 15, in the BC class A amplifier A therein, during a signal period of this input signal, produce by first power amplifier provide power output to this common load impedance to the conversion of power output to this common load is provided by second power amplifier.
19. by the power amplifier circuit of claim 15, in the BC class A amplifier A therein:
This input signal carries out amplitude modulation(PAM) by a modulation signal; And
The amplitude of the modulation signal that response changes from one first incoming level to, second incoming level produce by first power amplifier provide power output to this common load impedance to the conversion of power output to this common load is provided by second power amplifier.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US08/321,446 US5570062A (en) | 1994-10-12 | 1994-10-12 | AM-FM transmitter power amplifier using class-BC |
| US08/321,446 | 1994-10-12 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1168749A CN1168749A (en) | 1997-12-24 |
| CN1063892C true CN1063892C (en) | 2001-03-28 |
Family
ID=23250646
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN95196600A Expired - Fee Related CN1063892C (en) | 1994-10-12 | 1995-10-10 | AM-FM transmitter power amplifier using class-BC |
Country Status (11)
| Country | Link |
|---|---|
| US (2) | US5570062A (en) |
| EP (1) | EP0787381B1 (en) |
| KR (1) | KR100376081B1 (en) |
| CN (1) | CN1063892C (en) |
| AU (1) | AU691363B2 (en) |
| BR (1) | BR9509325A (en) |
| CA (1) | CA2202464C (en) |
| DE (1) | DE69522335T2 (en) |
| FI (1) | FI971515A (en) |
| MX (1) | MX9702579A (en) |
| WO (1) | WO1996012342A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104426382A (en) * | 2013-08-29 | 2015-03-18 | 住友电气工业株式会社 | Transformer |
| CN104467446A (en) * | 2013-09-12 | 2015-03-25 | 住友电气工业株式会社 | Transformer device |
| US10116197B2 (en) | 2014-11-05 | 2018-10-30 | Sumitomo Electric Industries, Ltd. | Transformer without magnetic coupling, electromagnetic induction or mutual inductance |
| US10122288B2 (en) | 2014-11-05 | 2018-11-06 | Sumitomo Electric Industries, Ltd. | Transformer composed of a front stage circuit and a rear stage circuit |
Families Citing this family (24)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10116732A (en) * | 1996-10-09 | 1998-05-06 | Nec Corp | Transmission line transformer and amplifier unit employing it |
| FI107658B (en) * | 1997-06-02 | 2001-09-14 | Nokia Mobile Phones Ltd | Bias voltage controlled parallel active components |
| DE19846069A1 (en) | 1998-10-06 | 2000-04-13 | Siemens Ag | Transmitter for a mobile phone |
| DE69833635T2 (en) | 1998-12-14 | 2007-01-18 | Alcatel | Amplification arrangement with voltage amplification and reduced power consumption |
| US6864668B1 (en) | 1999-02-09 | 2005-03-08 | Tropian, Inc. | High-efficiency amplifier output level and burst control |
| US6377784B2 (en) | 1999-02-09 | 2002-04-23 | Tropian, Inc. | High-efficiency modulation RF amplifier |
| US6366177B1 (en) | 2000-02-02 | 2002-04-02 | Tropian Inc. | High-efficiency power modulators |
| US6294955B1 (en) * | 2000-04-07 | 2001-09-25 | Harris Corporation | Apparatus and method for use in disconnecting and/or replacing one of a plurality of power amplifiers in a transmitter while the transmitter is operating |
| US6556053B2 (en) * | 2001-02-06 | 2003-04-29 | Harman International Industries, Incorporated | Half-bridge gate driver optimized for hard-switching |
| US6472936B1 (en) * | 2001-05-14 | 2002-10-29 | National Semiconductor Corporation | Low-noise gain switching circuit using tapped inductor |
| US6665525B2 (en) | 2001-05-29 | 2003-12-16 | Ericsson Inc. | High-level modulation method and apparatus |
| US6545541B2 (en) | 2001-05-29 | 2003-04-08 | Ericsson Inc. | Power amplifier embedded cell bias detection, methods of detecting bias in power amplifiers and systems utilizing embedded cell bias detection |
| US20040100376A1 (en) * | 2002-11-26 | 2004-05-27 | Kimberly-Clark Worldwide, Inc. | Healthcare monitoring system |
| US7889787B2 (en) * | 2003-08-04 | 2011-02-15 | Supertex, Inc. | Ultrasound transmit beamformer integrated circuit and method |
| US7129784B2 (en) * | 2004-10-28 | 2006-10-31 | Broadcom Corporation | Multilevel power amplifier architecture using multi-tap transformer |
| KR101126411B1 (en) | 2004-12-31 | 2012-03-28 | 삼성전자주식회사 | Fully Integrated Efficiency Enhanced Small Form Factor CMOS Power Amplifier |
| US7764210B2 (en) * | 2006-12-20 | 2010-07-27 | Texas Instruments Incorporated | System and method for converting an input signal |
| US7728661B2 (en) * | 2008-05-05 | 2010-06-01 | Javelin Semiconductor, Inc. | Controlling power with an output network |
| US7768350B2 (en) * | 2008-12-30 | 2010-08-03 | Javelin Semiconductor, Inc. | Output gain stage for a power amplifier |
| EP2226932B1 (en) | 2009-03-02 | 2013-10-16 | Alcatel Lucent | Method for amplifying a signal by a power amplifier, power amplifier system, device, computer program product, and digital storage medium thereof |
| WO2010133969A1 (en) | 2009-05-19 | 2010-11-25 | Marvell World Trade Ltd. | Circuits and methods combining signal power |
| US8786381B2 (en) | 2010-06-28 | 2014-07-22 | Avago Technologies General Ip (Singapore) Pte. Ltd. | Transformer structures for a power amplifier (PA) |
| JP5989578B2 (en) * | 2013-03-14 | 2016-09-07 | 株式会社東芝 | High frequency broadband amplifier circuit |
| CN104851425B (en) * | 2015-05-30 | 2018-11-30 | 宁波摩米创新工场电子科技有限公司 | A kind of high definition speech recognition system based on symmetrical transistor amplifier |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4401954A (en) * | 1980-08-14 | 1983-08-30 | Sony Corporation | Power amplifier |
| US5258714A (en) * | 1991-10-15 | 1993-11-02 | Sierra Semiconductor Corporation | Virtual current sensing system |
Family Cites Families (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3579136A (en) * | 1965-12-13 | 1971-05-18 | George A Machamer | Multi-stage power amplifier in which each stage conducts for only a predetermined portion of the input |
| US3577092A (en) * | 1968-07-09 | 1971-05-04 | Collins Radio Co | Signal path series step-biased multidevice high-efficiency amplifier |
| US3832643A (en) * | 1972-09-21 | 1974-08-27 | Raytheon Co | Minimal dissipation power controller |
| JPS5422859B2 (en) * | 1972-12-30 | 1979-08-09 | ||
| CH609181A5 (en) * | 1975-06-12 | 1979-02-15 | Bbc Brown Boveri & Cie | |
| JPS5252353A (en) * | 1975-10-24 | 1977-04-27 | Hitachi Ltd | Amplifier |
| JPS5255358A (en) * | 1975-10-31 | 1977-05-06 | Hitachi Ltd | Output amplifier |
| JPS5255357A (en) * | 1975-10-31 | 1977-05-06 | Hitachi Ltd | Output amplifier |
| US4158179A (en) * | 1976-04-19 | 1979-06-12 | Trio Kabushiki Kaisha | Amplifier circuit |
| SU594576A1 (en) * | 1976-05-10 | 1978-02-25 | Предприятие П/Я В-2634 | Push-pull power amplifier |
| US4117418A (en) * | 1977-01-14 | 1978-09-26 | Lennart Harry Erik Hoglund | Electric amplifier |
| SE412670B (en) * | 1978-02-07 | 1980-03-10 | Hoglund Lennart Harry Erik | ELECTRICAL AMPLIFIER |
| US4236120A (en) * | 1978-05-24 | 1980-11-25 | Harris Corporation | High speed, high efficiency amplifier circuit |
| US4319199A (en) * | 1979-12-20 | 1982-03-09 | Tektronix, Inc. | Efficient power amplifier with staggered power supply voltages |
| BG33422A1 (en) * | 1980-04-29 | 1983-02-15 | Vasilev | Power amplifier class bc |
| JPS58136117A (en) * | 1982-02-08 | 1983-08-13 | Pioneer Electronic Corp | Amplifier circuit |
| US4472688A (en) * | 1982-06-09 | 1984-09-18 | Trio Kabushiki Kaisha | Amplifier circuit |
| JPS6091868A (en) * | 1983-10-24 | 1985-05-23 | Trio Kenwood Corp | Power source circuit |
| US4959873A (en) * | 1988-07-08 | 1990-09-25 | The Marconi Company Limited | Transmission line switch |
| US5239275A (en) * | 1989-08-04 | 1993-08-24 | Motorola, Inc. | Amplitude modulator circuit having multiple power supplies |
| JPH0775324B2 (en) * | 1989-08-18 | 1995-08-09 | 日本電気株式会社 | Portable radio |
| US4994757A (en) * | 1989-11-01 | 1991-02-19 | Motorola, Inc. | Efficiency improvement of power amplifiers |
| US5175871A (en) * | 1991-08-08 | 1992-12-29 | Ericsson/Ge Mobile Communication Holding Inc. | Power amplifier for a cellular telephone |
| US5251331A (en) * | 1992-03-13 | 1993-10-05 | Motorola, Inc. | High efficiency dual mode power amplifier apparatus |
| CA2108461C (en) * | 1992-03-13 | 1999-09-07 | Dale G. Schwent | Power amplifier combining network |
-
1994
- 1994-10-12 US US08/321,446 patent/US5570062A/en not_active Expired - Lifetime
-
1995
- 1995-10-10 AU AU39453/95A patent/AU691363B2/en not_active Ceased
- 1995-10-10 CN CN95196600A patent/CN1063892C/en not_active Expired - Fee Related
- 1995-10-10 KR KR1019970702409A patent/KR100376081B1/en not_active IP Right Cessation
- 1995-10-10 CA CA002202464A patent/CA2202464C/en not_active Expired - Fee Related
- 1995-10-10 BR BR9509325A patent/BR9509325A/en not_active Application Discontinuation
- 1995-10-10 EP EP95937309A patent/EP0787381B1/en not_active Expired - Lifetime
- 1995-10-10 WO PCT/US1995/012485 patent/WO1996012342A1/en active IP Right Grant
- 1995-10-10 DE DE69522335T patent/DE69522335T2/en not_active Expired - Fee Related
- 1995-10-10 MX MX9702579A patent/MX9702579A/en not_active IP Right Cessation
-
1996
- 1996-05-06 US US08/643,364 patent/US5652546A/en not_active Expired - Lifetime
-
1997
- 1997-04-11 FI FI971515A patent/FI971515A/en unknown
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4401954A (en) * | 1980-08-14 | 1983-08-30 | Sony Corporation | Power amplifier |
| US5258714A (en) * | 1991-10-15 | 1993-11-02 | Sierra Semiconductor Corporation | Virtual current sensing system |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104426382A (en) * | 2013-08-29 | 2015-03-18 | 住友电气工业株式会社 | Transformer |
| TWI625034B (en) * | 2013-08-29 | 2018-05-21 | Sumitomo Electric Industries | Transformer |
| CN104426382B (en) * | 2013-08-29 | 2018-06-08 | 住友电气工业株式会社 | Transformer |
| CN104467446A (en) * | 2013-09-12 | 2015-03-25 | 住友电气工业株式会社 | Transformer device |
| CN104467446B (en) * | 2013-09-12 | 2018-12-28 | 住友电气工业株式会社 | Potential device |
| US10693387B2 (en) | 2013-09-12 | 2020-06-23 | Sumitomo Electric Industries, Ltd. | Transformer |
| US10116197B2 (en) | 2014-11-05 | 2018-10-30 | Sumitomo Electric Industries, Ltd. | Transformer without magnetic coupling, electromagnetic induction or mutual inductance |
| US10122288B2 (en) | 2014-11-05 | 2018-11-06 | Sumitomo Electric Industries, Ltd. | Transformer composed of a front stage circuit and a rear stage circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| FI971515A (en) | 1997-06-09 |
| WO1996012342A1 (en) | 1996-04-25 |
| KR100376081B1 (en) | 2003-06-11 |
| EP0787381B1 (en) | 2001-08-22 |
| CA2202464C (en) | 2005-06-28 |
| FI971515A0 (en) | 1997-04-11 |
| CN1168749A (en) | 1997-12-24 |
| CA2202464A1 (en) | 1996-04-25 |
| AU691363B2 (en) | 1998-05-14 |
| BR9509325A (en) | 1997-10-14 |
| DE69522335D1 (en) | 2001-09-27 |
| AU3945395A (en) | 1996-05-06 |
| MX9702579A (en) | 1997-07-31 |
| US5570062A (en) | 1996-10-29 |
| DE69522335T2 (en) | 2002-05-08 |
| US5652546A (en) | 1997-07-29 |
| EP0787381A1 (en) | 1997-08-06 |
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